You can probably use /etc/NetworkManager/dispatcher.d/01ifupdown (which was installed on my system by default) as reference. Using ifup to detect the status of eth2 seems like the right way to do it. You can then inform NetworkManager to connect to your VPN through the command-line client, nmcli. Is that enough to get you started?

You can probably use /etc/NetworkManager/dispatcher.d/01ifupdown (which was installed on my system by default) as reference. Using ifup to detect the status of eth2 seems like the right way to do it. You can then inform NetworkManager to connect to your VPN through the command-line client, nmcli. Is that enough to get you started?

Somewhat....

nmcli dev doesnt show my openvpn BUT nmcli con does.....What should I use?

The UUID is generated by NetworkManager. If you create a connection, delete it, then recreate it, NetworkManager will assign it a different UUID. The UUID is merely a way for NetworkManager to uniquely identify the network connections it has stored. It is not sensitive information like your MAC address, which is permanently embedded into your network card.